Catheters capable of pulling manipulation wires to perform bending manipulation of a distal part have been suggested. It is possible to bend the distal part bent inside a body cavity or at a branch point, thereby selecting an insertion direction.
PTL 1 discloses a catheter including a manipulating mechanism referred to as a dial part. Two manipulation wires branching from a tubular main body are mounted around the dial part in opposite directions and fixed thereto. The tubular main body (sheath) of the catheter is pulled out to a base end side of a manipulation-part main body through a lower part of the dial part, and a position adjusting mechanism and a hub connector are provided in the tubular main body. The position adjusting mechanism is a mechanism that moves the hub connector and the tubular main body forward and backward relative to the manipulation-part main body and the manipulation wires, thereby adjusting the tension of the manipulation wires. More specifically, the position adjusting mechanism is capable of being screwed in a forward-backward direction with respect to the manipulation-part main body, and when the position adjusting mechanism is moved forward with respect to the manipulation-part main body, a distal end of the tubular main body moves forward. Since tips of the manipulation wires are fixed to the distal end of the tubular main body, as the position adjusting mechanism moves forward, the tips of the manipulation wires also move forward. Meanwhile, base ends of the manipulation wires are fixed to the dial part of the manipulation part. For this reason, as the position adjusting mechanism moves forward, loosening of the manipulation wires is removed or the tension thereof is increased. On the contrary, when the position adjusting mechanism is moved backward with respect to the manipulation-part main body, the tips of the manipulation wires are moved backward together with the distal end of the tubular main body. Accordingly, the manipulation wires are loosened or the tension thereof is decreased.
The tubular main body of the catheter of PTL 1 is formed by combining an inner layer and an outer layer made of resin, and a metallic reinforcing layer that reinforces these layers. The reinforcing layer is formed by braiding metallic thin wires in the shape of a mesh. Meanwhile, in order to obtain high breaking strength, a metallic single wire or a metallic stranded wire is used for the manipulation wires.
[PTL 1] Japanese Unexamined Patent Application, First Publication No. 2010-253125